US5134885A - Circuit arrangement for measuring a mechanical deformation, in particular under the influence of a pressure - Google Patents

Circuit arrangement for measuring a mechanical deformation, in particular under the influence of a pressure Download PDF

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Publication number
US5134885A
US5134885A US07/579,939 US57993990A US5134885A US 5134885 A US5134885 A US 5134885A US 57993990 A US57993990 A US 57993990A US 5134885 A US5134885 A US 5134885A
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United States
Prior art keywords
temperature
dependent
signal
circuit
deformation
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Expired - Fee Related
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US07/579,939
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English (en)
Inventor
Hans Hecht
Winfried Kuhnt
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Robert Bosch GmbH
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Robert Bosch GmbH
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B7/00—Measuring arrangements characterised by the use of electric or magnetic techniques
    • G01B7/16—Measuring arrangements characterised by the use of electric or magnetic techniques for measuring the deformation in a solid, e.g. by resistance strain gauge
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L1/00—Measuring force or stress, in general
    • G01L1/20—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress
    • G01L1/22—Measuring force or stress, in general by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress using resistance strain gauges
    • G01L1/2268—Arrangements for correcting or for compensating unwanted effects
    • G01L1/2281—Arrangements for correcting or for compensating unwanted effects for temperature variations
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
    • G01L9/02—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means by making use of variations in ohmic resistance, e.g. of potentiometers, electric circuits therefor, e.g. bridges, amplifiers or signal conditioning
    • G01L9/06—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means by making use of variations in ohmic resistance, e.g. of potentiometers, electric circuits therefor, e.g. bridges, amplifiers or signal conditioning of piezo-resistive devices
    • G01L9/065—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means by making use of variations in ohmic resistance, e.g. of potentiometers, electric circuits therefor, e.g. bridges, amplifiers or signal conditioning of piezo-resistive devices with temperature compensating means

Definitions

  • the invention relates to a circuit arrangement for measuring a mechanical deformation and having a pressure sensor which, under the influence of a mechanical signal, emits an analog deformation-dependent signal.
  • German Utility Model 81 19 025 discloses a sensor for detecting the pressure of a medium and having at least one element the resistance of which varies under the influence of pressure.
  • a conventional commercially available resistor component preferably a carbon-film resistor, a thin-film resistor or a thick-film resistor is used.
  • the elements are preferably disposed in a bridge circuit, and to compensate for temperature factors and to increase the pressure-dependent signal, resistor components having different temperature and pressure coefficients are used. It is also proposed that resistor elements be disposed on a substrate that is elastically deformable in response to pressure, so that the simultaneous action of pressure and expansion or compression of the resistor component cause a signal increase.
  • the temperature characteristic of the output signal of the circuit arrangement is first calculated or plotted.
  • the temperature characteristic can be represented mathematically as a function dependent on the temperature, which in turn can be developed into a power-series expansion.
  • the linear member of the temperature characteristic it is sufficient for the linear member of the temperature characteristic to be compensated for, since the higher-order members are sufficiently small with respect to an allowable tolerance.
  • provisions must be made to compensate for quadratic and sometimes even higher components of temperature characteristic.
  • the actual compensation is then generally such that a separate temperature-dependent signal is formed within the circuit arrangement, and this signal is suitably added to or subtracted from the output signal.
  • the circuit arrangement of the aforedescribed type comprising a summing amplifier, a temperature-dependent coupling resistor through which the deformation-dependent signal is applied to the summing amplifier to compensate for the temperature characteristic of the measuring sensitivity, a temperature sensor composed of a network of temperature-dependent resistors which are arranged for compensating the linear and square components of the temperature characteristic of the circuit arrangement.
  • the circuit arrangement according to the invention has the advantage over the circuit arrangements known from the prior art in that not only a compensation of the static temperature characteristic is effected, but the temperature characteristic of the measuring sensitivity is also compensated for at the same time. This compensation of the temperature characteristic of the measuring sensitivity will be attained by supplying the output signal of the pressure sensor via a temperature-dependent resistor to an amplifier and the following circuit.
  • a further particularly great advantage of the circuit arrangement according to the invention consists in that the quadratic component of the temperature characteristic is compensated for by a portion of the circuit arrangement comprising solely resistor components. These components can accordingly be particularly simply produced by thick-film techniques using resistor pastes having various temperature coefficients, with optional subsequent trimming with a laser beam.
  • FIGURE of the drawing shows a circuit diagram of a circuit arrangement according to the invention.
  • the circuit arrangement shown in the drawing is operated between two supply voltage terminals U + and U - .
  • the terminal U - represents the ground of the circuit arrangement, while a stabilized feed voltage of 5 V is applied to the terminal U + .
  • a capacitor C1 connected between the supply voltage terminals serves to protect against voltage peaks that may arise, for instance originating in the ignition system.
  • a resistor bridge circuit R1, R2, R3, R4 Connected between the supply voltage terminals is a resistor bridge circuit R1, R2, R3, R4, the diagonal connections of which lead to the inputs of a measuring amplifier V1, which is an operational amplifier. Specifically, the junction point of the resistors R1, R2 leads to the inverting input, and the junction point of the resistors R3, R4 leads to the non-inverting input of the measuring amplifier V1.
  • the output of the measuring amplifier V1 is fed back via an adjustable resistor R7 to the inverting input.
  • the resistors R5, R6 and R7 are adjustable resistors, for example thick-layer-resistors which can be adjusted by laser-adjustment.
  • the resistors R1, R2, R3, R4 together form an arrangement for measuring a mechanical deformation under the influence of a pressure, that means, that they form a pressure sensor such as that known from German Utility Model 81 19 025.
  • the resistors are located on a thick-film membrane and are disposed in such a manner that, when the pressure is exerted upon the membrane, the resistors R1, R4 are deformed by compression, while the resistors R2, R3 are stretched in length. Because of a piezoresistive effect of the thick-film resistor paste from which the resistors R1, R2, R3, R4 are formed, their change in resistance is approximately 8 times as great as their geometric change in length.
  • the resistor bridge circuit Since the resistor bridge circuit is operated at a constant voltage, an imbalance of the bridge occurs when pressure is exerted upon the thick-film membrane, and this imbalance is expressed as the appearance of a diagonal voltage of the bridge, which is supplied to the measuring amplifier V1.
  • the amplification factor of the arrangement is adjusted with the resistor R7, while a desired offset is adjusted with the resistance divider R5, R6.
  • the output of the measuring amplifier V1 is connected with the resistor R8, which is also connected with the supply voltage terminal U + so that the current needed for the measuring amplifier V1 is furnished via the resistor R8.
  • the measuring amplifier V1 and the resistors R5-R8 are the signal-amplifying stage in which the output-voltage of the resistor bridge is amplified.
  • the resistor bridge circuit exhibits a temperature effect, which is yielded in the diagonal voltage of the bridge and which is also amplified in the signal-amplifying stage V1, R5-R8, but which is not desirable for pressure measurement.
  • This temperature effect is composed of a temperature characteristic of the pressure measurement sensitivity and a temperature response of the offset of the circuit arrangement.
  • the temperature characteristic of the offset has a curved course, which is approximately composed of a linear and a quadratic component.
  • the output of the measuring amplifier V1 leads via a temperature-sensitive series circuit of two resistors R23(-), R24, where the coupling resistor R23(-) has a negative temperature coefficient, that means, that with increasing temperature, the resistance becomes smaller and the resistor R28 is an adjustable resistor, to the inverting input of a summing amplifier V2. Because the resistance R23(-) has a negative temperature coefficient, it is possible, to compensate the temperature characteristic of the sensitivity by the series-connection of R23(-) and R24.
  • the amplification factor of the second amplifier V2 is defined via an adjustable resistor R28, which is connected between the output and the inverting input of the summing amplifier V2.
  • the output of the summing amplifier V2 is connected to an output terminal U out of the circuit arrangement.
  • the output current of the circuit arrangement is obtained via a resistor R30, which is connected between the supply voltage terminal U + and the output of the summing amplifier V2.
  • the series circuit of the two adjustable resistors R11, R12 is also connected between the terminal U + and the terminal U - .
  • the junction point of the resistors R11, R12 Via the divider ratio of the resistors R11, R12, a coarse adjustment of the input voltage offset of the summing amplifier V2 can be performed. a fine adjustment of the offset is possible with three resistors R13, R14, R25.
  • the adjustable resistors R13, R14 are connected in series between the terminals U + and U - , while their junction point is connected via the resistor R25 to the inverting input of the summing amplifier V2.
  • the series circuit of a resistor R29 and a capacitor C2 is connected parallel to the adjustable feedback resistor R28. Furthermore, the non-inverting input is connected via a resistor R9 and a capacitor C3, and the inverting input is connected via a resistor R10 and a capacitor C4, to the ground of the circuit at the terminal U - .
  • the remaining portion of the circuit arrangement shown in the drawing serves as temperature sensor and serves the purpose of temperature characteristic compensation of the offset of the arrangement R1-R4 and R7, R8, V1.
  • This offset consists of one part, which is linearly dependent on the temperature and another part, which is quadratically dependent on the temperature.
  • the temperature-dependent series circuit of two resistors R15, R16 is connected between the terminals U + and U - , and the junction point of these resistors is connected via an adjustable resistor R26 to the inverting input of the summing amplifier V2.
  • a temperature-dependent resistor bridge circuit R17(+), R18(-), R19(-), R20(+) is connected between the terminals U + and U - , and a series circuit of two temperature dependent resistors R21(+), R22(-) is additionally disposed in its bridge diagonal, between the junction points of the temperature-dependent resistors R17(+), R18(-) and the temperature-dependent resistors R19(-), R20(+).
  • the junction point of the temperature-dependent resistors R21(+), R22(-) leads via an adjustable resistor R27 likewise to the inverting input of the summing amplifier V2.
  • the resistors R17, R20 and R21 are temperature-dependent and adjustable.
  • the output signal of the measuring amplifier V1 can be represented approximately by the following equation:
  • the equation shows terms, which are linearly dependent on the temperature, quadratically dependent on the temperature and linearly dependent on the pressure and the temperature.
  • the temperature-dependent signals are generated in the circuit arrangement by providing the resistors formed by thick-film techniques, using resistor pastes which have their own positive or negative temperature coefficients.
  • the resistors R15(+), R17(+), R21(+), R20(+) have a positive temperature coefficient
  • the resistors R23(-), R16(-), R18(-), R19(-), R22(-) have a negative temperature coefficient.
  • the symbols (+), (-) in the disclosure and the drawing symbolizes positive or negative temperature coefficients of the resistors.
  • the linear temperature member of the output signal of the amplifier V1 is now compensated for with the aid of the resistors R15, R16, R26.
  • the quadratic temperature member is compensated for by the resistors R17-R22 and R27.
  • the component dependent on both pressure and temperature is compensated for with the resistors R23, R24.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Measuring Fluid Pressure (AREA)
  • Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
US07/579,939 1986-04-16 1990-09-07 Circuit arrangement for measuring a mechanical deformation, in particular under the influence of a pressure Expired - Fee Related US5134885A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3612810 1986-04-16
DE19863612810 DE3612810A1 (de) 1986-04-16 1986-04-16 Schaltungsanordnung zur messung einer mechanischen verformung, insbesondere unter einwirkung eines drucks

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
US07402999 Continuation-In-Part 1989-09-05

Publications (1)

Publication Number Publication Date
US5134885A true US5134885A (en) 1992-08-04

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ID=6298802

Family Applications (1)

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US07/579,939 Expired - Fee Related US5134885A (en) 1986-04-16 1990-09-07 Circuit arrangement for measuring a mechanical deformation, in particular under the influence of a pressure

Country Status (6)

Country Link
US (1) US5134885A (de)
EP (1) EP0264388B1 (de)
JP (1) JPS63503085A (de)
KR (1) KR880701362A (de)
DE (2) DE3612810A1 (de)
WO (1) WO1987006339A1 (de)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6853237B2 (en) * 2001-03-27 2005-02-08 Mitsubishi Denki Kabushiki Kaisha Temperature-coefficient-generating circuit and temperature-compensating circuit using the same
WO2006051081A1 (de) * 2004-11-11 2006-05-18 Bosch Rexroth Ag Schaltungsanordnung zum messen einer mechanischen verformung
US20110080220A1 (en) * 2009-10-07 2011-04-07 Taiwan Semiconductor Manufacturing Co., Ltd. Temperature compensated integrator
US20160258826A1 (en) * 2015-03-03 2016-09-08 Denso Corporation Sensor driving device
WO2020263175A1 (en) * 2019-06-25 2020-12-30 Choon How Lau Circuit arrangement and method of forming the same

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3814950A1 (de) * 1988-05-03 1989-11-16 Bosch Gmbh Robert Beschleunigungsaufnehmer
DE3908795A1 (de) * 1989-03-17 1990-09-20 Bosch Gmbh Robert Verfahren und vorrichtung zur messung einer mechanischen verformung
JP3071202B2 (ja) * 1989-07-19 2000-07-31 富士電機株式会社 半導体圧力センサの増巾補償回路
JPH03255926A (ja) * 1990-03-06 1991-11-14 Ulvac Japan Ltd ピラニ真空計
DE4041621A1 (de) * 1990-12-22 1992-07-02 Bosch Gmbh Robert Auswerteschaltung fuer einen piezoresistiven drucksensor
DE4107433C2 (de) * 1991-03-08 2000-09-21 Bosch Gmbh Robert Verfahren und Vorrichtung zur Sensorsignalaufbereitung
DE4115288C2 (de) * 1991-05-10 1995-05-04 Bosch Gmbh Robert Einrichtung zum Abgleich von Exemplarstreuung und Temperatureinflüssen mindestens eines Sensors
DE4135393A1 (de) * 1991-10-26 1993-04-29 Bosch Gmbh Robert Einrichtung zur weg- oder winkelmessung
JPH0550334U (ja) * 1991-12-11 1993-07-02 エヌオーケー株式会社 歪みゲージセンサの温度補償回路
DE4210818C2 (de) * 1992-04-01 2002-02-14 Bosch Gmbh Robert Auswerteschaltung für einen Sensor, insbesondere für einen piezoresistiven Drucksensor
JP4466509B2 (ja) * 2005-08-25 2010-05-26 株式会社デンソー コモンレール式燃料噴射システムの制御装置
DE102011085555A1 (de) 2011-11-02 2013-05-02 Robert Bosch Gmbh Variable Widerstandsanordnung, Messbrückenschaltung und Verfahren zum Kalibrieren einer Messbrückenschaltung

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3528022A (en) * 1965-10-14 1970-09-08 Gen Electric Temperature compensating networks
US4667516A (en) * 1985-01-30 1987-05-26 Siemens Aktiengesellschaft Circuit arrangement for compensating for the temperature dependence of the sensitivity and the null point of a piezoresistive pressure sensor
US4813272A (en) * 1986-08-01 1989-03-21 Hitachi, Ltd. Semiconductor pressure sensor
US4836027A (en) * 1986-11-25 1989-06-06 Vdo Adolf Schindling Ag Circuit for a sensor

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS4925984A (de) * 1972-04-12 1974-03-07
JPS56140229A (en) * 1980-04-02 1981-11-02 Toshiba Corp Pressure converter
US4478527A (en) * 1982-12-02 1984-10-23 General Signal Corporation Temperature compensation for zero and span changes in a measurement circuit

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3528022A (en) * 1965-10-14 1970-09-08 Gen Electric Temperature compensating networks
US4667516A (en) * 1985-01-30 1987-05-26 Siemens Aktiengesellschaft Circuit arrangement for compensating for the temperature dependence of the sensitivity and the null point of a piezoresistive pressure sensor
US4813272A (en) * 1986-08-01 1989-03-21 Hitachi, Ltd. Semiconductor pressure sensor
US4836027A (en) * 1986-11-25 1989-06-06 Vdo Adolf Schindling Ag Circuit for a sensor

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
"Integrated Pressure Transducer", Measurement Techniques, vol. 20, No. 5, May 1977, Vaganov et al., pp. 706-707.
Integrated Pressure Transducer , Measurement Techniques, vol. 20, No. 5, May 1977, Vaganov et al., pp. 706 707. *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6853237B2 (en) * 2001-03-27 2005-02-08 Mitsubishi Denki Kabushiki Kaisha Temperature-coefficient-generating circuit and temperature-compensating circuit using the same
WO2006051081A1 (de) * 2004-11-11 2006-05-18 Bosch Rexroth Ag Schaltungsanordnung zum messen einer mechanischen verformung
US20110080220A1 (en) * 2009-10-07 2011-04-07 Taiwan Semiconductor Manufacturing Co., Ltd. Temperature compensated integrator
US8013657B2 (en) * 2009-10-07 2011-09-06 Taiwan Semiconductor Manufacturing Co., Ltd. Temperature compensated integrator
US20160258826A1 (en) * 2015-03-03 2016-09-08 Denso Corporation Sensor driving device
US10054502B2 (en) * 2015-03-03 2018-08-21 Denso Corporation Sensor driving device
WO2020263175A1 (en) * 2019-06-25 2020-12-30 Choon How Lau Circuit arrangement and method of forming the same

Also Published As

Publication number Publication date
EP0264388B1 (de) 1990-01-03
WO1987006339A1 (en) 1987-10-22
EP0264388A1 (de) 1988-04-27
DE3761341D1 (de) 1990-02-08
DE3612810A1 (de) 1987-10-22
JPS63503085A (ja) 1988-11-10
KR880701362A (ko) 1988-07-26

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